Self Contained Foam Dispenser

ABSTRACT

A self-contained foam dispensing device includes a casing, a mixing chamber, a port adapted to receive one or more containers including a plurality of chemicals in a plurality of compartments and a flow generator adapted to induce flow of chemicals from the compartments toward a mixing chamber, the flow generator being located between the mixing chamber and the port. When the one or more containers are in the port the one or more containers move with movement of the casing.

RELATED APPLICATIONS

The present application claims the benefit under 35 U.S.C. 119(e) ofU.S. provisional application 60/556,883, titled “Hand-Held Dispenser”,filed Mar. 29, 2004, the disclosure of which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to foam dispensers and particularly tohand held foam dispensers.

BACKGROUND OF THE INVENTION

Foam materials are commonly used for packaging. The foam is generallygenerated by mixing two chemical components, which harden within about10-30 seconds. In many cases, a foam dispensing gun is used to generatethe foam at the packaging site. U.S. Pat. No. 4,262,848 to Chabria andU.S. Pat. No. 5,462,204 to Fiin, the disclosures of which areincorporated herein by reference, describe such guns which are connectedthrough tubes to large containers including the chemicals used informing the foam. The dispensing gun generally includes a pair of pumpswhich pump the chemicals out of the containers at precise requiredamounts in order to achieve a proper mix. In addition, the chemicals maybe heated in order to achieve a better mix reaction.

U.S. Pat. No. 3,178,157 to Cole, the disclosure of which is incorporatedherein by reference, describes a compact foaming apparatus for varioustasks, such as inflating a raft. The foaming apparatus includes twotanks which receive flexible bags that carry the chemicals to be mixedin forming the foam. A pressure source is used to compress the bags andcause the chemicals to leave the bags.

U.S. Pat. No. 6,691,898 to Hurray et al., the disclosure of which isincorporated herein by reference, describes a hand-held dispensingapparatus for urethane foams, which is claimed to allow one handedoperation. The apparatus includes a pen-shaped dispenser connectedthrough tubes to a pair of chemical containing pressurized containers. Abutton on the pen-shaped dispenser is used to actuate release of thechemicals from the pressurized containers.

U.S. Pat. No. 5,348,392 to Bouquet et al., the disclosure of which isincorporated herein by reference, describes a hand-held apparatus formixing two chemicals from two separate receptacles. The apparatusincludes piercing means for piercing the receptacles, a mixing chamberand a passageway for expelling the foam. The apparatus is used formedical purposes and is actuated by direct mechanical pressure of a useron the receptacles to extract the chemicals therefrom.

The above hand-held apparatus are generally inaccurate in theproportions of chemicals they mix and provide a low quality foam mix.

As foam materials harden within a short time, remnants of the foam mayharden within the dispensing apparatus and clog flow passageways.

U.S. Pat. No. 6,079,868 to Rydell, the disclosure of which isincorporated herein by reference, describes a hand-held device formixing and delivering a curable biomaterial in a minimally invasivemedical procedure. In one embodiment of Rydell, the device pumps thechemicals it mixes from remote containers connected through tubes to thedevice. In another embodiment of Rydell, the device has containersmounted on it and the chemicals are extracted using pressure. Thematerials used for generating foam are different from those used inbiomedical applications. In addition, a delivery conduit is required inmedical applications but not in packaging applications. The Rydelldevice uses a relatively long static mixer for mixing the chemicals,which needs to be replaced after every use.

SUMMARY OF THE INVENTION

A general aspect of some embodiments of the invention relates to aself-contained foam dispensing device, i.e., a dispensing device havingchemical containers mounted on or included in the device, which provideshigh quality foam mixing. The dispensing device optionally allowsintermittent use in small amounts over a relatively long period, withreduced waste and/or reduced element replacement costs. Optionally, thecompact dispensing device is hand-held, along with foam chemicalcontainers.

An aspect of some embodiments of the invention relates to aself-contained dispensing device for generating foam, which includes atleast one pump, or other flow generator, located between the chemicalcontainers and a mixing chamber of the device. The pump between thechemical containers and the mixing chamber provides more accurate and/orefficient operation, than provided by pressure units for pushingchemicals out of their containers, located behind the containers. Inaddition, using a pump between the containers and the mixing chamberallows use of non-rigid containers such as plastic bags or elastic bags.Having the pump between the containers and the mixing chamber alsoallows for a more compact dispensing device and allows simplerreplacement of the pump and the mixing chamber in cases of problems. Insome embodiments of the invention, the pump is connected to a nozzledefining the mixing chamber.

In some embodiments of the invention, the at least one pump at leastpartially sucks the chemicals used in generating the foam out of thechemical containers. Pumping the chemicals out of their containersallows, in some cases, more accurate control of the mixed quantities,than pushing the chemicals out of their containers. In some embodimentsof the invention, the self-contained dispensing device includes at leastone metering pump. Alternatively or additionally, the at least one pumpincludes a gear pump. In some embodiments of the invention, the pumpcomes in contact with the chemicals. Alternatively, the pump operateswithout any of its parts coming in contact with the chemicals, forexample, the pump may comprise a peristaltic pump.

In some embodiments of the invention, the pumping provides accuratechemical amounts with an error of up to about 2-5% of the pumped amount,or even less. Pumping the chemicals also allows easily reaching highpressure levels, which can be used for high quality mixing of thechemicals. Furthermore, using pumping reduces the amount of chemicalremnants settling along the chemical paths in the dispensing device. Insome embodiments of the invention, a pushing mechanism is used inaddition to the pumping. The pushing mechanism optionally provides acoarse force applied to the chemicals, while the pumping provides theaccurate control of the chemical mix. In some embodiments of theinvention, the pushing mechanism is used only when a new container isused, in order to remove any air between the chemicals and the pump andstart the pumping from a new container. Alternatively or additionally,the pushing mechanism operates whenever the dispensing device isoperated, in order to remove any air bubbles, which may interfere withthe pumping, from the chemicals.

In some embodiments of the invention, the self contained dispensingdevice includes a heater, which heats the chemicals used in generatingfoam, to an optimal temperature level for the foam creation.

Optionally, the self-contained dispensing device is a hand-held device.Optionally, the dispensing device can be held and operated using onlyone hand. In some embodiments of the invention, the device is worn onthe user's hand and/or includes a support structure for placing thedispensing device on the user's arm. The device is optionally lightweight, for example having a weight of less than 5 kilograms includingthe chemical containers mounted in the device. Optionally, when usingsmall chemical containers, the dispensing device including the chemicalcontainers has a weight of less than 3 kilograms or even 2 kilograms. Insome embodiments of the invention, the device has small dimensions,optionally having a longest dimension of less than 40-60 centimeters oreven less.

In other embodiments of the invention, the dispensing device is a tablemounted device or a wall mounted device.

In some embodiments of the invention, the device includes substantiallyclosed compartments which receive the chemical containers, such thatduring use of the device, the chemical containers are not seen by theuser. Optionally, the closed compartments are adapted to receivecontainers of different sizes, for example by limiting the number offaces of the compartments to which the chemical containers areconnected. In some embodiments of the invention, the chemical containersconnect only to a single face of the compartments in which they reside.Alternatively to including the chemical containers in closedcompartments, the chemical containers are mounted externally on thedispensing device. In some embodiments of the invention, the device doesnot include tubes that are external to a housing of the device. Thus,there is no need to drag tubes and/or no need to be careful to avoidexternal tubes getting stuck on bulging objects. Furthermore, havingvery short internal tubes, if at all, reduces the chances of tubesgetting clogged.

The chemical containers are optionally rigid, so that their handling issimpler than the handling of bags. Optionally, the end of the containeropposite an outlet from the container (or a side) is movable, to allowpushing the contents of the container toward the outlet from which thechemical is pumped. Alternatively, chemical bags are used, as bags aregenerally cheaper than rigid containers.

An aspect of some embodiments of the invention relates to a foamdispensing device having a permanently usable base portion which doesnot come in contact with the chemicals used to generate the foam (evenbefore they are mixed) and a detachable portion which includes all theparts that come in contact with the chemicals. The detachable portion isoptionally adapted for easy release and replacement, for example withoutusing tools and/or without requiring substantial application of force.Optionally, the entire detachable portion can be replaced together as asingle part. In some embodiments of the invention, the detachableportion is replaceable using a single hand, for example when the baseportion is table mounted.

In some embodiments of the invention, the detachable portion is formedof inexpensive disposable materials. In an exemplary embodiment of theinvention, the detachable portion is formed substantially only fromplastic.

The base portion of the dispensing device optionally includes a motorwhich provides the power for inducing the flow of chemicals into themixing chamber. Alternatively or additionally, the base portion includesat least one heater, for heating the chemicals. In some embodiments ofthe invention, the base portion includes a control panel and/or acontroller which controls the operation of the dispensing device. Thebase portion optionally includes batteries and/or a power transformerfor operating the dispensing gun.

In some embodiments of the invention, the detachable portion includes anozzle in which the chemicals are mixed and one or more pumps or otherflow generator which induces the flow of the chemicals into the mixingchamber. Possibly, the detachable portion further includes at least onecontainer of chemicals which is an integral part of the detachableportion. Optionally, kits including replacement detachable portions areprovided within stand alone packages. The kits optionally include allthe elements of the detachable portion connected to each other, suchthat there is no need to assemble the detachable portion beforeconnecting the detachable portion to the base portion.

An aspect of some embodiments of the invention relates to a replacementpart kit for a dispensing gun, which includes both a flow generator(e.g., a chemical pump or suction unit) and a mixing chamber.Optionally, the flow generator and mixing chamber are attached withinthe kit. In some embodiments of the invention, the flow generator andmixing chamber are not adapted for separation without tools.

An aspect of some embodiments of the invention relates to aself-contained dispensing device for generating foam, which has adetachable portion in which the chemicals forming the foam mix together.The detachable portion allows fast replacement of elements of thedispensing device that were clogged by settling foam. Optionally, asingle detachable portion of the dispensing device includes all theelements of the device that come in contact with the chemicals afterthey are mixed and/or on which hardened foam remnants may settle. Theremaining parts of the dispensing device are optionally designed forlong term use. Optionally, the remaining parts include relativelyexpensive elements, such as a heater, a motor and/or electroniccircuits.

An aspect of some embodiments of the invention relates to a heating basefor storing and pre-heating chemical containers used in generating foam.The heating base optionally pre-heats the containers so that the timerequired to warm the chemicals within a dispensing gun is short and/orthe energy consumption for heating by the dispensing device is low. Insome embodiments of the invention, the heating base also has areceptacle adapted to receive the dispensing gun. Optionally, theheating base has one or more receptacles adapted to receive relativelysmall chemical tanks, for example having a content of less than 10liters, less than 5 liters or even less than 2 liters.

An aspect of some embodiments of the invention relates to a foamdispensing device adapted to receive chemical containers having a portwith a flexible and/or elastic valve. The elastic valve preventschemicals from exiting the container unless a matching tube leading thechemical to a mixing chamber of the dispensing device is properlypositioned in the valve.

An aspect of some embodiments of the invention relates to a selfcontained chemical bag for producing a foam. The bag includes at leasttwo compartments which separately store chemicals used in generating thefoam, and a third compartment in which the chemicals are mixed. In someembodiments of the invention, the bag includes a nozzle between themixing compartment and the chemical compartment, which nozzle controlsthe mixing of the chemicals, to achieve a high quality mix. In someembodiments of the invention, one or more disposable pumps are includedin the nozzle. The use of self-contained bags allows cleaner operationof foam generation, as the entire mixing of the chemicals may occurwithin the bag.

There is therefore provided in accordance with an exemplary embodimentof the invention, a self-contained foam dispensing device, comprising acasing, a mixing chamber, a port adapted to receive one or morecontainers including a plurality of chemicals in a plurality ofcompartments, such that when the one or more containers are in the portthe one or more containers move with movement of the casing and a flowgenerator adapted to induce flow of chemicals from the compartmentstoward a mixing chamber, the flow generator being located between themixing chamber and the port.

Optionally, the flow generator comprises a pump. Optionally, thedispensing device is designed to be hand held, with the one or morecontainers, by a user. Optionally, the one or more containers comprisetwo containers. Optionally, the one or more containers comprise a singlecontainer divided into a plurality of compartments. Optionally, thecasing defines one or more recesses adapted to receive the containerswithin the casing. Optionally, the recesses are adapted to receivecontainers of a plurality of different sizes, operatively connected tothe port.

Optionally, the dispensing device with the one or more full containers,weighs less than 5 kilograms. Optionally, the flow generator comprisesseparate pumps for each of the chemicals. Optionally, the flow generatorincludes one or more sets of suction gears. Optionally, the flowgenerator pumps the chemicals out of the containers at different rates.Optionally, the chemicals pumped by the flow generator reach a pressureabove 5 atmospheres. Optionally, the device includes one or more heatersadapted to heat the chemicals in the containers. Optionally, the deviceincludes one or more heaters adapted to heat the chemicals flowing fromthe containers. Optionally, the mixing chamber is detachably attached tothe casing. Optionally, the device includes a nozzle through which themixed chemicals are released to the environment. Optionally, the nozzlecomprises a material to which foam does not substantially adhere.Optionally, the walls of the nozzle are flexible. Optionally, the nozzleis usable over a plurality of separate foam generating sessions.Optionally, the compartments are substantially rigid. Optionally, themixing chamber is defined by flexible walls.

Optionally, the mixing chamber is expanded by the pressure of streams ofchemicals pumped from the containers. Optionally, the mixing chamber isexpanded from a substantially zero volume when the suction unit is notoperating to a larger volume, when the section unit is operating.Optionally, the device includes at least one pressure valve along thepath from the containers to the mixing chamber. Optionally, the deviceincludes at least one pusher adapted to push the chemicals in the atleast one container toward an exit of the container.

There is further provided in accordance with an exemplary embodiment ofthe invention, a foam dispensing device, comprising a casing, a portadapted to receive one or more containers including a plurality ofchemicals in a plurality of compartments, and a detachable foam mixingchamber, easily detachable from the casing without use of tools, inwhich chemicals from the plurality of compartments are mixed, thedispensing device with the one or more containers is hand held.

Optionally, substantially all portions of the dispensing device thatcome in contact with the chemicals after they are mixed are included ina single detachable element with the mixing chamber. Optionally, thedevice includes a heater for heating the chemicals in the compartments.Optionally, the device includes a motor within the casing which operatesone or more pumps to pump the chemicals from the compartments to themixing chamber.

There is further provided in accordance with an exemplary embodiment ofthe invention, a base for a foam dispensing device, comprising a nichefor receiving the dispensing device, a battery charger adapted to chargea battery of the dispensing device while the dispensing device is in theniche, at least one compartment for receiving a container including achemical used in generating foam by the dispensing device and a heateradapted to heat the contents of the container in the at least onecompartment.

Optionally, the base includes at least one storage compartment forreceiving a chemical container, wherein the chemical in the container inthe storage compartment is not substantially heated while in the storagecompartment.

There is further provided in accordance with an exemplary embodiment ofthe invention, a bag for generating foam, comprising a plurality of bagchemical compartments separately including chemicals which mix togetherinto foam, an empty bag compartment and a nozzle coupled to the bagadapted to lead the chemicals from the plurality of chemicalcompartments to the empty compartment in a maimer which causes thechemicals to mix and turn into foam. Optionally, the bag includes adisposable pump coupled to the bag. Optionally, the empty compartmenthas a sufficient volume to accommodate foam generated by mixing most ofthe chemicals in the plurality of chemical compartments.

Optionally, the bag includes at least one tube leading from the chemicalcompartment to the empty compartment, which tube is adapted to operatewith a peristaltic pump.

There is further provided in accordance with an exemplary embodiment ofthe invention, a foam dispensing device, comprising a mixing chamber, aflow generator adapted to induce flow of chemicals to the mixingchamber, the flow generator being included in a single replaceable partwith the mixing chamber; and a base portion, including a motor, whichbase portion only includes elements that do not come in contact with thechemicals.

Optionally, the base portion includes a heater. Optionally, the singlereplaceable part is detachable from the base portion without use oftools.

BRIEF DESCRIPTION OF THE DRAWINGS

Particular exemplary embodiments of the invention will be described withreference to the following description of embodiments in conjunctionwith the figures, wherein identical structures, elements or parts whichappear in more than one figure are generally labeled with a same orsimilar number in all the figures in which they appear, in which:

FIG. 1 is a schematic illustration of a foam generating and dispensingsystem, in accordance with an exemplary embodiment of the invention;

FIG. 2 is a cross-sectional view of a dispensing gun, in accordance withan exemplary embodiment of the invention;

FIG. 3 is a schematic view of elements forming a suction unit, inaccordance with an exemplary embodiment of the invention;

FIG. 4 is a cut away assembled schematic view of a suction unit and anozzle, in accordance with an exemplary embodiment of the invention;

FIGS. 5A and 5B are cross-sectional views of an exit portion of thedispensing gun of FIG. 2, in accordance with an exemplary embodiment ofthe invention;

FIG. 6 is a schematic view of a nozzle of a dispensing gun, inaccordance with another exemplary embodiment of the invention;

FIG. 7 is a schematic illustration of a dispensing system, in accordancewith another exemplary embodiment of the invention;

FIG. 8 is a schematic view of a stand for a foam dispensing gun, inaccordance with an exemplary embodiment of the invention;

FIG. 9 is a schematic illustration of a table-mounted self-containedfoam dispensing device, in accordance with an exemplary embodiment ofthe invention;

FIGS. 10A and 10B illustrate a chemical container port for use in adispensing device, in closed and open states, respectively, inaccordance with an exemplary embodiment of the invention; and

FIG. 11 is a schematic illustration of a foam generation machine, inaccordance with an exemplary embodiment of the invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

FIG. 1 is a schematic illustration of a foam generating and dispensingsystem 100, in accordance with an exemplary embodiment of the invention.System 100 comprises a base 110 which includes a recess 112 sized andshaped to receive a hand-held foam dispensing gun 120. Optionally, abattery (not shown) of gun 120 is charged when the gun is properlyplaced in recess 112. Base 110 optionally further includes a pluralityof recesses 130 adapted to receive chemical containers, and heat thecontainers while they are in the recesses. In an exemplary embodiment ofthe invention, recesses 130 host containers 132 of a chemical A, e.g.,and containers 134 of a chemical B. In an exemplary embodiment of theinvention, chemical A comprises a polymeric isocyanate or afluorocarbon, while chemical B comprises polyols, catalysts or flameretardants. It is noted, however, that system 100 is not limited to usewith any specific chemicals and has advantages which are useful formixing many chemicals. Particularly, the materials from which system 100is formed are optionally selected according to the chemicals beingmixed. Alternatively or additionally, the size of containers 132 and 134may be selected according to the specific chemicals used. For example,rather than using containers of same sizes, containers of differentsizes may be used, according to the mixing ratio of the chemicals or toprevent placing the containers in the wrong compartments.

Optionally, a switch 140 is used to activate the heating in recesses130. In some embodiments of the invention, the heating is applied to allthe recesses 130. Alternatively, the heating is applied only to a singlepair of recesses 130 which are known by the operator, such that theoperator takes replacement containers from those recesses. The heatingoptionally brings the chemicals to an optimal temperature for improvedmixing viscosity. Alternatively, the heating brings the chemicals to atemperature lower than optimal and the remaining temperature increase iscompleted within gun 120. In some embodiments of the invention, thecontainers 132 and 134 are heated in recesses 130 to a temperature whichdoes not prevent the user from holding the containers and loading theminto gun 120. Optionally, the heating in base 110 is controlled by athermostat. Alternatively, the heating is performed, for simplicity,without a controller.

Gun 120 includes a housing 160 with a removable cover 162, which allowsreplacing containers 132 and 134 as described hereinbelow. Optionally,gun 120 includes a handle 164 for holding gun 120 and an activationtrigger 166 on handle 164. In some embodiments of the invention, astabilization structure 150 protrudes from the bottom side 168 of gun120 spaced from handle 164. When held by a user, structure 150optionally rests on the user's arm, thus stabilizing gun 120 on theuser's arm and allowing for accurate aiming of the foam released fromthe gun, while gun 120 is held with only one hand. In some embodimentsof the invention, gun 120 weighs less than 5 Kg, or even less than 3 Kgwhen containers 132 and 134 are full. In an exemplary embodiment of theinvention, gun 120 has dimensions of about 50×18×8 centimeters.

In some embodiments of the invention, gun 120 includes a control panel170 which allows a user to set various operation attributes of the gun.Alternatively or additionally, the operation attributes of gun 120 canbe set from a control panel not on gun 120, for example a control panelon base 110, on a computer (not shown) connected to base 110 or on aremote control. Control panel 170 may include, for example, mixingratios of the chemicals, the heating temperature and/or the desiredoperation rate. Alternatively or additionally to allowing the setting ofoperation attributes, control panel 170 displays the status of gun 120,such as the charging level of the battery and/or the remaining amount ofchemicals in the containers.

Alternatively to using stabilizing structure 150, gun 120 may include astrap or a rigid bracelet which is used to connect the gun to the user'sarm. Further alternatively or additionally, handle 164 is replaced by anindention, a ring, a strap and/or any other holding and/or attachmentmechanism. Gun 120 optionally has a structure that allows it to beeasily balanced on the user's hand,

FIG. 2 is a cross-sectional view of gun 120, in accordance with anexemplary embodiment of the invention. Gun 120 includes a body section202 adapted to receive containers 132 and 134. A plurality of heatingelements 206 optionally surround containers 132 and/or 134 so as to heatthe contents of the containers to an optimal temperature for foamgeneration. A suction unit 210 pumps the chemicals from containers 132and 134 through channels 212 and 214, respectively. The chemicals aremixed and ejected through a nozzle 220. Optionally, the mixing of thechemicals is performed within a cavity defined in an exit unit 392(FIGS. 5A and 5B) within suction unit 210. When gun 120 is operated,motor 260 optionally rotates a driving shaft 262, which in turn powersthe suction, as described below with reference to FIG. 3.

In some embodiments of the invention, containers 132 and 134 have movingrear walls 232 and 234, which are pushed by respective screws 226 and228, so that sufficient chemical amounts within containers 132 and 134are located adjacent channels 212 and 214. A screw motor 240 optionallyactuates the movement of screws 226 and 228. The force applied by screwmotor 240 to screws 226 and 228 is not intended to override theoperation of suction unit 210, but rather only forces the chemicalswithin containers 132 and 134 toward the inlets of suction unit 210.Screws 226 and 228 optionally achieve a relatively low flow pressure,while suction unit 210 achieves a higher pressure at its exit. In someembodiments of the invention, a clutch mechanism (not shown) disconnectsmotor 140 from one or both of screws 226 and 228 when the force from themotor is not required in one or both of the containers. Optionally,screw motor 240 operates whenever suction unit 210 is operated.Alternatively, screw motor 240 operates only when suction unit 210encounters problems in pumping sufficient material. Alternatively tousing separate motors 240 and 260, a single motor is used to rotate bothshaft 262 and screws 226 and 228.

Alternatively or additionally to using screw motor 240 and/or screws 226and 228, other mechanisms for pushing the chemicals in containers 132and 134 toward suction unit 210 may be used, such as one or moresprings.

In some embodiments of the invention, gun 120 is powered by a battery282. Alternatively or additionally, gun 120 is powered by a connectionto an electrical socket.

Body section 202 may be configured to receive containers 132 and 134 ofonly a single size. Alternatively, body section 202 is adapted toreceive containers 132 and 134 of a plurality of different sizes. Thus,the consumer can choose the container size to be used, according to theexpected amount of foam he/she will require in the near future. It isnoted, however, that even after containers 132 and 134 are opened, thereis no problem leaving them unused for a few days and they can be usedagain immediately thereafter. In some embodiments of the invention, thecontainers 132 and 134 have different sizes and/or different ports, toavoid connecting the wrong container to one or both the ports.

FIG. 3 is a schematic view of the elements forming suction unit 210, inaccordance with an exemplary embodiment of the invention. Suction unit210 includes three boards 310, 312 and 314, which hold the variousmoving elements of suction unit 210. Driving shaft 262 optionally passesthrough holes 316 and 318 in boards 310 and 312 to a first set ofsuction gears 322 and 324, which pump a chemical from container 134.Gears 352 and 354 between boards 310 and 312 transfer the rotation forceof shaft 262 to a second set of suction gears 362 and 364, which pump achemical from container 132. In some embodiments of the invention, theratio between gears 352 and 354 defines the ratio of the volume of thechemicals pumped from containers 132 and 134.

Suction gears 322 and 324, as well as suction gears 362 and 364,optionally operate in accordance with the operation methods of gearmetering pumps known in the art. Optionally, the suction gears have arelatively high accuracy with an error level of up to about 2-5%, forexample 3%, of the desired pumped quantities. The chemicals fromcontainers 132 and 134 enter suction unit 210 through channels 372 and374 optionally carved in board 314 and through respective holes inboards 310 and 312. From channels 372 and 374, the chemicals passthrough mesh gears and holes 382 and 384 into a mixing chamber definedbetween a circular unit 390 and exit unit 392, which includes nozzle220.

FIG. 4 is a schematic cut-open view of suction unit 210 (FIG. 3),circular unit 390 and exit unit 392, in accordance with an exemplaryembodiment of the invention. In FIG. 4, circular unit 390 is shown inplace within boards 312 and 314. An internal piece 393 sits withincircular unit 390 and attaches to exit unit 392. In addition, FIG. 4shows the path leading from hole 382, through a bore 389, to a channelbetween internal piece 393 and exit unit 392, as discussed below withreference to FIG. 5A.

FIG. 5A is a cross-sectional view of circular unit 390, internal piece393 and exit unit 392, in accordance with an exemplary embodiment of theinvention. During operation, the chemical flow in bore 389 enters anarrow channel 516 passing within exit unit 392. Similarly, the chemicalfrom the other container flows into a narrow channel 514, within exitunit 392. The chemical flows exit narrow channels 514 and 516 near a tip510 of internal piece 393, and press against a valve defined by oppositelips 508 of exit unit 392. The pressure on lips 508, due to highpressure from the pumps, causes lips 508 to separate, as shown in FIG.5B, which is a variation of FIG. 5A in which the pressure of thechemicals form at least a portion of a mixing chamber 598. The chemicalsfrom narrow channels 514 and 516 enter mixing chamber 598 and mixtogether. From mixing chamber 598, the mixed chemicals flow out nozzle220 into their desired packing location according to the direction ofgun 120. When suction gears 322 and 324 stop their operation, thepressure on lips 508 stops and they return back into their closedposition (FIG. 5A), preventing settling of foam within mixing chamber598.

Lips 508 serve as flexible walls which define mixing chamber 598, whenthe walls are expanded by the pressure of the chemicals exiting narrowchannels 514 and 516. A potential advantage of using a flexible wall isthat it reduces the amount of mixed chemicals that can settle withinchamber 598 and hence the amount of foam remnants hardening in chamber598 is small. In some embodiments of the invention, exit unit 392 may beused for a plurality of foam dispensing sessions, which occur atdifferent times separated by hours, days or even weeks. In addition,lips 508 serve as a valve which prevents dripping of material whensuction unit 210 stops operating.

In some embodiments of the invention, when the chemicals are not pumpedout of the containers, the volume of mixing chamber 598 is substantiallyzero, due to the return of lips 508 back into their rest position (FIG.5A). Alternatively, the closing of lips 508 closes a portion of chamber598 nearer channels 514 and 516. The remaining portion of chamber 598 isopen to the environment. Optionally, any settling of foam in nozzle 220can be easily removed by pressing the walls of nozzle 220 by a humanoperator. As shown in FIGS. 5A and 5B, the streams in narrow channels514 and 516 are not directed at lips 508 but rather at tip 510.Therefore, a relatively high chemical pressure is required in order toopen a passageway to mixing chamber 598. In other embodiments of theinvention narrow channels 514 and 516 are more directly pointed at lips508, thus reducing the pressure level required in order to open thelips.

In some embodiments of the invention, the high pressure of the chemicalstreams has a double purpose. On the one hand, the pressure opens mixingchamber 598 and the path out of suction unit 210 to nozzle 220. On theother hand, the pressure is used in achieving a high quality mix of thechemicals.

Nozzle 220 is optionally formed of a flexible but durable material, suchthat the walls of nozzle 220 can be pressed together in order to removefoam remnants that settled in the nozzle, if such remnants remain. Insome embodiments of the invention, nozzle 220 is elastic. The pressinggenerally grinds the foam remnants or at least causes them to detachfrom the nozzle. Alternatively or additionally, nozzle 220 is formed ofa material to which foam remnants do not stick or at least have arelatively weak bonding. In an exemplary embodiment of the invention,nozzle 220 is formed of Teflon, delarin and/or polypropylene. In otherembodiments of the present invention, polypropylene, polyethylene and/orsilicon are used.

Nozzle 220 is optionally flared in order to minimize the settling of themixed chemicals on walls of the nozzle. In some embodiments of theinvention, nozzle 220 has two parallel relatively rigid walls 398 (FIG.3), connected by two more flexible walls. When pressed on, the flexiblewalls move and collapse, while the rigid walls compress the foamremnants. In some embodiments of the invention, flexible walls 396 (FIG.3) have a central folding line 397 (FIG. 3). Alternatively, nozzle 220has a circular and/or conical shape. Nozzle 220 has an expanding shapetoward its outlet to the environment, so that it is relatively easy toremove foam remnants from the nozzle (e.g., by allowing simple accesswith a screwdriver or other tool) and hardening foam remnants are notcaught tightly between the walls of the nozzle. Optionally, nozzle 220does not include corners and/or enclaves in which foam remnants cansettle. Nozzle 220 optionally has a length and/or width sufficientlylarge to receive the fingers of a user and allow the user to pressagainst the walls in order to remove foam remnants therefrom.

In some embodiments of the invention, exit unit 392 is designed to allowfast release and connection of exit unit 392 from and to circular unit390. Alternatively or additionally, exit unit 392 and circular unit 390are designed to allow their fast connection and/or release from and tothe remaining portion of suction unit 210. Circular unit 390 and/or exitunit 392 are optionally easily replaced, when necessary, for example dueto clogging by settlement of foam remnants.

It is noted that, in some embodiments of the invention, the chemicalsfrom containers 132 and 134 are mixed only in exit unit 392, such thatfoam remnants can settle only within these easily replaced pieces. Aslips 508 serve as valves which only allow passage of the chemicals whenthe chemicals are provided in relatively high pressure streams, themixed chemicals cannot backflow into suction unit 210. Typically, aftereach 5-10 uses and/or when the operation is problematic (e.g., the mixis not good, the stream is weal), exit unit 392 is replaced. In someembodiments of the invention, the mixed chemicals also touch the tip 510of internal piece 393. Optionally, in these embodiments, internal piece393 is also easily replaceable, for example every 10-20 or even every100 uses. Alternatively, chamber 598 is defined closer to nozzle 220, sothat the mixed chemicals only touch portions of exit unit 392, which iseasily replaceable.

Alternatively to replacing only exit unit 392, internal piece 393 orcircular unit 390, nozzle 220 is replaced as a single unit, forsimplicity of maintenance. In some embodiments of the invention, nozzle220 is integral with suction unit 210, such that suction unit 210 andnozzle 220 are replaced together. In some embodiments of the invention,kits including containers 132 and 134, nozzle 220 and suction unit 210are provided. The elements of the kits are optionally providedassembled, allowing fast replacement of the elements of dispensing gun120 that come in contact with the chemicals. Thus, whenever there is aproblem in operation of gun 120 the user simply replaces a singledetachable unit including all the elements that come in contact with thechemicals, and there is no need to analyze the cause of the problem.

In some embodiments of the invention, the chemicals are provided bysuction unit 210 at a high pressure, such as between 6-10 atmospheres(e.g., 6.079-10.13 bar), so as to achieve a smooth mix of the chemicals.

Heaters 206 are optionally controlled to achieve a desired chemical heatof the contents of containers 132 and/or 134, such as between about50-60°. Alternatively, for simplicity, heaters 206 are not controlledand perform the heating according to a predetermined operation patternand/or the heat transfer characteristics of gun 120. For example,heaters 206 may be operated periodically and/or whenever suction unit210 is operated. Heaters 206 optionally comprise twisted wire heaters,as is known in the art. Alternatively, other heating apparatus may beused, such as PTC heaters and/or heating rods. In some embodiments ofthe invention, heaters 206 range along the entire length of body section202, so as to heat all the material in containers 132 and 134.Alternatively, heaters 206 range only along a portion of body section202, for example the portion closer to suction unit 210. Optionally,heaters 206 cover substantially the entire circumference of containers132 and 134, along the length of the containers that they cover.Alternatively, heaters 206 cover only a portion of the circumference ofcontainers 132 and 134, as required to achieve a desired temperature.For example, for simplicity, in some embodiments of the invention, theside from which containers 132 and 134 are inserted into body section202 is not covered by heater 206. Optionally, the containers aredesigned to transfer the heat according to the positions of the heatersin gun 120 and/or recesses 130.

The amount of material pumped from each container is optionallycontrolled by the rate of rotation of the sets of suction gears 322 and324 and 362 and 364. Hence, the ratio between the amounts of the mixedmaterials is defined by the ratio between the sizes of gears 352 and354. Different chemicals may require different mixing ratios. In someembodiments of the invention, a customer can purchase dispensing system100 with a plurality of suction units 210 which differ substantivelyonly in the ratios between the radii of gears 352 and 354. Optionally,suction units 210 are easily replaceable according to the customer'sneeds. For example, a first suction unit 210 may be used for achieving arigid foam for packaging starters, alternators and/or computers, while asecond suction unit 210 is used for a softer packaging, for example forglass dishes. The different suction units 210 may be used with differentchemicals or with same chemicals. Alternatively to the customerreplacing suction units 210, the replacement is performed by a servicestation of a supplier of system 100, where suction units 210 or onlygears 352 and 354 are replaced.

FIG. 6 is a schematic view of a nozzle 600 of a dispensing gun, inaccordance with another exemplary embodiment of the invention. A bodyportion 602 of the dispensing gun includes two outlets 604 whichseparately provide streams of the chemicals, optionally of high pressureas discussed above. The streams are combined within nozzle 600 and areprovided through an outlet 606. Nozzle 600 is optionally easilyconnected to body portion 602 so as to allow easy and fast replacementof the nozzle. In some embodiments of the invention, body portion 602includes protruding plates 610, which receive compatible protrusions612. Optionally, nozzle 600 is attached to body portion 602 by bringingthe nozzle at a small angle to the proximity of plates 610 and rotatingthe nozzle so that protrusions 612 move into the handles (e.g., using abayonet connection method). Alternatively, the attachment is performedby squeezing nozzle 600 so that it passes into plates 610.

Alternatively to using passive nozzles 600, nozzles which includesuction unit 210 may be used. Thus, replacement of suction unit 210 fordifferent types of foams can be made simple.

Alternatively to providing a mixing chamber 598 in a nozzle connected tothe dispensing gun, in some embodiments of the invention, the dispensinggun provides two separate streams of the different chemicals. A mixingchamber is placed in a box to be packaged and the separate streams aredirected at this mixing chamber. The mixing chamber may include a cheapdisposable unit, such as a bag.

FIG. 7 is a schematic illustration of a dispensing system 700, inaccordance with another exemplary embodiment of the invention. In system700, the chemicals are held in containers mounted on the gun and not inclosed compartments within the gun. Dispensing system 700 comprises adispensing gun 720 having a port 725 to which a container 701 isconnected. Container 701 is optionally divided into two separatecompartments 721 and 722, each of which contains a different chemical orchemical mixture. Compartments 721 and 722 may be of the same size ormay have different sizes. In an exemplary embodiment of the invention,the ratio of the sizes of compartments 721 and 722 is equal to the mixratio of the materials they contain when they mix into foam. Thus, boththe compartments of container 701 empty out at substantially the sametime. It is noted that the orientation of container 701 and port 725 issuch that the contents of the container flow down into gun 720 withoutthe need for a pushing mechanism as in the gun of FIG. 2. Levers 709 areoptionally used to release container 701 for replacement.

When a trigger 706 is pressed, a valve 707 is opened, and the chemicalsfrom container 701 are allowed to flow through separate channels 702 and717 to a mixing chamber 704. It is noted that valve 707 may be close toport 725 and remote from mixing chamber 704 as shown in FIG. 7, or valve707 may be close to mixing chamber 704. Release levers 708(schematically represented in FIG. 7) allow fast removal of mixingchamber 704 and replacement with a new mixing chamber. Heaters 703 areoptionally used to heat the chemicals to a desired mixing and reactiontemperature. System 700 is optionally powered by an electrical cordconnection 705. Alternatively or additionally, system 700 may be poweredby a chargeable or non-chargeable battery.

Optionally, a piston 710 is used to increase the flow of the chemicalstoward mix chamber 704. Alternatively or additionally, a suction unit,as described above with reference to FIG. 3, may be used in order tocontrol the flow. It is noted, however, that in some embodiments of theinvention, suction is not used and the chemical flow is achieved by thepushing of piston 710 and/or by gravity.

Alternatively to system 700 using a single container 701 having twoseparate compartments, system 700 may include two separate containers.

FIG. 8 is a schematic illustration of a stand 800 for use with foamdispensing gun 120, in accordance with an exemplary embodiment of theinvention. Stand 800 may be used to fill packaging bags 810 bydispensing gun 120, instead of using gun 120 to directly place the foamin a package. Bags 810 optionally include filling ports 812 which areadapted to fit on a compatible reception port on the bottom side of anarm 820. Above the reception port, arm 820 includes an aperture and/orbase which firmly receives gun 120. In some embodiments of theinvention, bags 810 are foldable as shown in a bag pile 816. It is notedthat stand 800 may be used with dispensing guns other than dispensinggun 120, including guns that induce mixing in the bags.

While gun 120 is of a size allowing it to be hand-held, at least some ofthe aspects of the present invention are applicable also to other selfcontained dispensing devices, which are not hand-held, such as tablemounted devices. Using a self-contained dispensing device, which has thechemical containers placed therein or mounted thereon, requires lessspace and is more suitable for a small business than large dispensingdevices known in the art.

FIG. 9 is a schematic illustration of a table mounted self-containedfoam dispensing device 900, in accordance with an exemplary embodimentof the invention. Dispensing device 900 includes a housing 902 adaptedto receive two chemical containers 904 and 906. Optionally, chemicalcontainers 904 and 906 are inserted into housing 902 through a frontdoor 910. Alternatively, the chemical containers are inserted from aboveor behind. In some embodiments of the invention, control buttons 912 ondoor 910 are used to control the operation of device 900. A stand 920 isoptionally used to hold device 900 on a table or other surface, forconvenient use.

Device 900 further includes a pump 914 which pumps required amounts ofchemicals from containers 904 and 906 and a nozzle 916 in which thechemicals are mixed in order to generate foam 918. Nozzle 916 may be ofany of the types described above, any other type of nozzle known in theart and/or any of the nozzles described in a PCT application titled“Foam Dispenser Nozzle”, filed on same date as the present applicationin the Israel receiving office, and assigned to the assignee of thepresent application, the disclosure of which is incorporated herein byreference.

While device 900 can be used to direct foam directly into place and/orinto bags manually positioned beneath nozzle 916, FIG. 9 shows a bagloading system 930 for conveniently, manually or automatically, placingbags beneath nozzle 916. Bag loading system 930 includes a stick 932carrying a roll of empty bags and a rack 934 for holding bags openbeneath nozzle 916.

FIGS. 10A and 10B illustrate a chemical container port 950 for use in adispensing device, in closed and open states, respectively, inaccordance with an exemplary embodiment of the invention. A base flange952 of port 950 fits on a chemical container, such as containers 132 and134, and/or a chemical bag. In some embodiments of the invention, a tubereceptor 958 sits within port 950 and leads a respective tube 970 of thedispensing device 120, which leads the chemical from the container,through port 950 toward a mixing chamber of the dispensing device. In aclosed state of port 950, a diaphragm 960 blocks the passage ofchemicals through the port. When tube 970 is inserted into port 950,tube 970 fits over tube receptor 958 and folds diaphragm 960 inwards soas to allow flow of chemicals from the container into the dispensingdevice in the direction of an arrow 972. In its folded position,diaphragm 960 prevents flow of chemicals out of the container not intotube 970. Upon removal of tube 970 from port 950, diaphragm 960 unfoldsand prevents flow of chemicals out of the container.

In some embodiments of the invention, tube 970 is a part of a dispensingdevice. On an opposite end of port 950 from base flange 952, a lip 954of the port optionally abuts against the dispensing device.Alternatively, long tubes may lead from container port 950 to thedispensing device.

In some embodiments of the invention, a plastic ring 956 locatedradially within lip 954, holds diaphragm 960 in place.

In some embodiments of the invention, diaphragm 960 comprises a silicondiaphragm. Alternatively to a silicon diaphragm, any other material maybe used for diaphragm 960.

Port 950 is particularly useful in self-contained dispensing devices, inwhich it is particularly desired to prevent dripping of chemicals. It isnoted, however, that port 950 may be used also in other foam dispensingdevices.

FIG. 11 is a schematic illustration of a foam generation machine 980, inaccordance with an exemplary embodiment of the invention. Machine 980 isadapted for generation of foam bags from plastic bags 982 pre-filledwith chemicals. In some embodiments of the invention, bags 982 includetwo chemical compartments 984 and 986, which include required amounts ofchemicals for generating foam. An empty compartment 988 is adapted toreceive a mixture of the chemicals from compartments 984 and 986 and hassufficient volume to accommodate the foam resulting from expansion ofthe mixture. A disposable nozzle 990 is placed between chemicalcompartments 984 and 986 and empty compartment 988. It is noted thatnozzle 990 is emphasized and therefore seems to be above emptycompartment 988 rather than within compartment 988. It will beunderstood that nozzle 990 is within the compartment 988. Alternatively,tubes (not shown) lead the mixed chemicals from the mixing chamber ofnozzle 990 to compartment 988.

Nozzle 990 optionally includes embedded channels 992 which controllablylead the chemicals to a mixing chamber 994 therein. In some embodimentsof the invention, nozzle 992 is formed of a flexible, optionallycompressible, material which is preset in a closed configuration, suchthat absent external pressure to open the channels 992, chemicals do notflow through the nozzle. Possibly, a rigid ring (not shown) presses onnozzle 990 so as to keep channels 992 closed.

In order to generate foam, bag 982 is placed by a human user in machine980, in an orientation in which chemical compartments 984 and 986 are ona heating plate 996. A thermostat 995 optionally prevents the furtheroperation of machine 980, until the chemicals in compartments 984 and986 are sufficiently heated. Alternatively or additionally, a timerprevents further operation of machine 980, unless bag 982 is withinmachine 980 for at least a predetermined amount of time. After thechemicals are sufficiently heated, a press piston 998 is pressed down oncompartments 984 and 986, for example responsive to actuation of acontrol 997 by a human, and forces the chemicals through nozzle 990. Thepressure from piston 998 pushes chemical streams through channels 992 ata high pressure, partially due to the small cross-section of thechannels, such that the chemical streams have sufficient force to openthe channels and mix in mixing chamber 994.

The mixing of the chemicals is optionally performed within sufficienttime (e.g., less than 15 seconds) in order to allow for insertion of bag982 into a package before the foam hardens.

Alternatively or additionally to using piston 998 to force the chemicalsfrom compartments 984 and 986 into empty compartment 988, a pump is usedto push the chemicals at a sufficient pressure. In an exemplaryembodiment of the invention, bag 982 includes a disposable pumpincorporated therein. In operation, a motor on machine 980 is connectedto gears of the pump so as to operate the pump. Alternatively, a pump onmachine 980 is connected to nozzle 990 externally in a manner whichinduces flow of the chemicals through channels 992. Furtheralternatively, tubes connecting compartments 984 and 986 to emptycompartment 988 are oriented to operate with peristaltic pumps onmachine 980. In some embodiments of the invention, one or more rollersmay be used to force the chemicals out of compartments 984 and 986.

It will be appreciated that the above described methods may be varied inmany ways. It should also be appreciated that the above describeddescription of methods and apparatus are to be interpreted as includingapparatus for carrying out the methods and methods of using theapparatus.

The present invention has been described using non-limiting detaileddescriptions of embodiments thereof that are provided by way of exampleand are not intended to limit the scope of the invention. For example,in addition to, or instead of, lips 508, separate pressure valves may beplaced along the path to the mixing chamber in order to prevent backflow and/or operation at lower pressures than suitable. It should beunderstood that features and/or steps described with respect to oneembodiment may be used with other embodiments and that not allembodiments of the invention have all of the features and/or steps shownin a particular figure or described with respect to one of theembodiments. Variations of embodiments described will occur to personsof the art.

It is noted that some of the above described embodiments may describethe best mode contemplated by the inventors and therefore may includestructure, acts or details of structures and acts that may not beessential to the invention and which are described as examples.Structure and acts described herein are replaceable by equivalents whichperform the same function, even if the structure or acts are different,as known in the art. Therefore, the scope of the invention is limitedonly by the elements and limitations as used in the claims. When used inthe following claims, the terms “comprise”, “include”, “have” and theirconjugates mean “including but not limited to”.

1. A self-contained foam dispensing device, comprising: a casing; amixing chamber; a port adapted to receive one or more containersincluding a plurality of chemicals in a plurality of compartments, suchthat when the one or more containers are in the port the one or morecontainers move with movement of the casing; and a flow generatoradapted to induce flow of chemicals from the compartments toward amixing chamber, the flow generator being located between the mixingchamber and the port.
 2. A device according to claim 1, wherein the flowgenerator comprises a pump.
 3. A device according to claim 1, whereinthe dispensing device is designed to be hand held, with the one or morecontainers, by a user.
 4. A device according to claim 1, wherein the oneor more containers comprise two containers.
 5. A device according toclaim 1, wherein the one or more containers comprise a single containerdivided into a plurality of compartments.
 6. A device according to claim1, wherein the casing defines one or more recesses adapted to receivethe containers within the casing.
 7. A device according to claim 6,wherein the recesses are adapted to receive containers of a plurality ofdifferent sizes, operatively connected to the port.
 8. A deviceaccording to claim 1, wherein the dispensing device with the one or morefull containers, weighs less than 5 kilograms.
 9. A device according toclaim 1, wherein the flow generator comprises separate pumps for each ofthe chemicals.
 10. A device according to claim 1, wherein the flowgenerator includes one or more sets of suction gears.
 11. A deviceaccording to claim 1, wherein the flow generator pumps the chemicals outof the containers at different rates.
 12. A device according to claim 1,wherein the chemicals pumped by the flow generator reach a pressureabove 5 atmospheres.
 13. A device according to claim 1, comprising oneor more heaters adapted to heat the chemicals in the containers.
 14. Adevice according to claim 1, comprising one or more heaters adapted toheat the chemicals flowing from the containers.
 15. A device accordingto claim 1, wherein the mixing chamber is detachably attached to thecasing.
 16. A device according to claim 1, comprising a nozzle throughwhich the mixed chemicals are released to the environment.
 17. A deviceaccording to claim 16, wherein the nozzle comprises a material to whichfoam does not substantially adhere.
 18. A device according to claim 16,wherein the walls of the nozzle are flexible.
 19. A device according toclaim 16, wherein the nozzle is usable over a plurality of separate foamgenerating sessions.
 20. A device according to claim 1, wherein thecompartments are substantially rigid.
 21. A device according to claim 1,wherein the mixing chamber is defined by flexible walls.
 22. A deviceaccording to claim 1, wherein the mixing chamber is expanded by thepressure of streams of chemicals pumped from the containers.
 23. Adevice according to claim 22, wherein the mixing chamber is expandedfrom a substantially zero volume when the flow generator is notoperating to a larger volume, when the flow generator is operating. 24.(canceled)
 25. A device according to claim 1, comprising at least onepusher adapted to push the chemicals in the at least one containertoward an exit of the container. 26-29. (canceled)
 30. A base for a foamdispensing device, comprising: a niche for receiving the dispensingdevice; a battery charger adapted to charge a battery of the dispensingdevice while the dispensing device is in the niche; at least onecompartment for receiving a container including a chemical used ingenerating foam by the dispensing device; and a heater adapted to heatthe contents of the container in the at least one compartment. 31-35.(canceled)
 36. A foam dispensing device, comprising: a mixing chamber; aflow generator adapted to induce flow of chemicals to the mixingchamber, the flow generator being included in a single replaceable partwith the mixing chamber; and a base portion, including a motor, whichbase portion only includes elements that do not come in contact with thechemicals.
 37. A device according to claim 36, wherein the base portionincludes a heater.
 38. A device according to claim 36, wherein thesingle replaceable part is detachable from the base portion without useof tools.
 39. A chemical container, comprising: a container including apolymeric isocyanate or a fluorocarbon, suitable for use in generating afoam; and a port on the container, through which the content of thecontainer may flow out of the container, the port being covered by adiaphragm and adapted to receive a respective tube into which thecontent of the container flows, wherein the diaphragm prevents flow fromthe container when a tube is not in the port and prevents drippingoutside the tube, when the tube is in the port.
 40. A containeraccording to claim 39, wherein the container has a volume of less than 5liters.